Risk factors for delayed bleeding after endoscopic resection for large colorectal tumors

Endoscopic resection techniques for treating colorectal tumors have advanced recently so that large colorectal tumors can now be treated endoscopically, although some patients experience delayed bleeding after endoscopic resection. Our aim was to clarify the risk factors for delayed bleeding after endoscopic resection for colorectal tumors≥20 mm in diameter. Endoscopic submucosal dissection cases were excluded because of the low incidence of delayed bleeding after such procedures.

This was a retrospective study using a prospectively completed database and patient medical records at a single, national cancer institution. A total of 403 colorectal endoscopic resections were performed on 375 consecutive patients. We analyzed the database and retrospectively assessed patient age, gender, hypertension and current use of anticoagulant (warfarin) or antiplatelet drugs (e.g. aspirin, ticlopidine) as well as tumor location, size, macroscopic type, histopathological findings, resection method and whether or not placement of prophylactic clips was performed during the endoscopic resection.

The overall rate of delayed bleeding was 4.2% (17/403) and the median interval between endoscopic resection and the onset of delayed bleeding was 2 days (range, 1-14 days). All delayed bleeding cases were successfully controlled by endoscopic hemostasis involving clipping and/or electrocoagulation without the need for surgical interventions or blood transfusions. Based on our univariate analysis, the delayed bleeding rate was significantly higher in both males (P=0.04) and those patients without prophylactic clip placement (P=0.04).

Our study results indicated that prophylactic clip placement may be an effective method for preventing delayed bleeding after endoscopic resection for large colorectal tumors.